Front Master Cylinder - Is 14mm okay?

I'm upgrading from a cheapo Magura master cylinder. I've read that 13MM is a good size to use with a stock Norton caliper.

However, I've found a few on Ebay that will fit my narrow drag bars but they have 14mm pistons.

Will this work akay?

master cylinder ration chart

Here's a chart for master cylinder ratios on Vintage Brake's website.

http://www.vintagebrake.com/mastercylinder.htm

14mm front master cylinder

The stock master cylinder on my bike has been sleeved down to 12.5mm, works very well with the stock caliper, nice progressive feel and good stopping power, several people offer the service, Old Britts , British Bike Connection and others. Ride safely. James.